The prior art as disclosed in German Patent Document No. DE 27 46 490 C3 discloses a bridging device for expansion joints in which lamellae extending at right angles to the longitudinal axis of the traffic route are supported on traverses which are pivoted and movably supported at both sides in the joint edges and which diagonally bridge the joint. U-shaped bows are welded to the bottom of the lamellae, wherein elastic sliding drag bearings which are slewably connected with the lamellae and in which the traverses are movably guided are arranged in said U-shaped bows. In order to take up the horizontal force components occurring in the lamellae during the movement of the bridge superstructure, the traverses are alternately diagonal to each other. Thereby, the force components of the horizontal forces which are directed in the longitudinal direction of the lamellae neutralize each other so that there is no danger of a one-sided drifting of the lamellae.
The fact that the support distances of the lamellae are not uniform in this known construction has proven to be a particular disadvantage. As a result, a complicated reinforcement of the lamellae is required at those places in which the distances are larger in order to ensure the required flexural strength for loads occurring, for example, in heavy vehicle traffic. If the superstructure moves due to temperature influences, such as a creeping or contraction of the concrete, the traverses twist about a vertical axis. Due to the swivel, and traverses being arranged at an acute angle to the direction of movement of the superstructure, the angle between the swivel traverse and the direction of the lamellae or the two joint edges, respectively, changes when the joint gap is increased or reduced in size.